The objective of this research is to produce alumina-elastomer interpenetrating network composites having the advantages of the ceramic phase without the unpredictable strength and characteristic brittleness of such materials. The incorporated elastomer acts as an energy sink, removing the energy necessary to continue crack propagation, thus reducing the likelihood of fracture. The composites are being formed both by impregnating the host ceramic matrix with monomer and polymerizing, in situ, using chemical initiation and by loading polymer melts directly into the matrix. The major applications of the new composites will be as biomaterials. They should prove useful for construction of implant devices such as hips, knees, shoulders, finger joints and oral appliances.